I am not sure if this will help you at all but if you go to sunbiz.org you maybe able to find so information on what you may need. I hope you find the info your looking for. Good luck with the new business

General liability insurance and workmans comp is critical. As far as license goes,,depends on what kind of sign work you are planning on doing? In Texas you have to have a master sign electrician to do electrical signs and register with the city. Check with the city buildign and planning folks, he can help you.